A story about how the bombing of Berlin destroyed the German computer revolution and handed the future to the Americans.
🔥 On the night of December 13, 1943, British bombers erased a block in central Berlin from the face of the earth, where in the basement of a house on Methfesselstrasse stood a machine whose existence the world would only learn about twenty years later. Z3 — the first fully functional programmable computer in history with binary system and floating point — turned into a pile of molten relays and charred punched tape. Its creator, 28-year-old self-taught engineer Konrad Zuse, was at that moment working on the fourth model in a workshop on the city outskirts, unaware that he had just lost the only material proof of his priority over ENIAC, Colossus, and all future heroes of American computer mythology.
⚙️ The paradox is that Z3 was ahead of its time by exactly enough to remain invisible to contemporaries. Built in 1941 — four years before ENIAC and eight years before EDSAC — it already possessed all the features of a computer in the modern sense: binary arithmetic, program control via punched tape, 22-bit floating point (7 bits exponent, 15 bits mantissa), 64 words of memory, frequency 5.3 Hz. But Nazi command denied Zuse funding, seeing no military value in his "arithmometer," and the Western world was too busy with its own war to notice a genius working in isolation in the middle of the enemy capital. When the bombs fell on Methfesselstrasse, computer history took a different path — Anglo-American, with Turing and von Neumann in leading roles, and Zuse remained a footnote in textbooks, acknowledged post factum.
🛠️ Konrad Zuse began building his first computer Z1 in 1936 in his parents' apartment on Methfesselstrasse, turning the living room into a workshop and the dining table into a drafting board. He was a 26-year-old graduate of the Technical University of Berlin, worked as a civil engineer at the aviation company Henschel, and hated the routine calculations of wing statics so much that he decided to build a machine to do it for him. Z1 was purely mechanical — 20 thousand metal plates, cut by hand with a jigsaw, driven by an electric motor from a vacuum cleaner. Memory — 16 words of 22 bits, arithmetic — binary with floating point, programming — punched tape, punched with a hole punch in the kitchen. The machine weighed nearly a ton, occupied 4 square meters, and operated at a frequency of 1 Hertz — one operation per second, provided the metal plates didn't jam from vibrations.
💰 Zuse financed the project out of his own pocket, borrowing from friends and relatives. Z1 cost him approximately 10 thousand Reichsmarks — the annual salary of a qualified engineer. The machine was completed in 1938, but worked extremely unreliably: mechanical parts, manufactured without machine tools and precision machining, constantly jammed, and Zuse had to disassemble the structure after every dozen operations. He realized that mechanics was a dead end and began experimenting with electromechanical relays, which were available thanks to the development of the telephone industry. Z2, built in 1940, retained the mechanical memory of Z1 but received a relay processor — 800 relays, capable of performing addition in 0.3 seconds, multiplication — in 3 seconds. The machine became more reliable, but still too slow for commercial use.
🎯 Z3, completed in May 1941, became Zuse's first fully relay-based machine and the first computer in history to meet all criteria of a modern computing machine. 2600 relays, 22-bit floating point, 64 words of memory, 8 instructions (addition, subtraction, multiplication, division, square root, load, store, conditional jump emulated manually through punched tape). Clock frequency — 5.3 Hz, multiplication in 3 seconds, division in 5 seconds. The machine consumed 4 kilowatts, made a deafening clatter of relays, and occupied a cabinet the size of a wardrobe. But the main thing — it worked stably, performed complex engineering calculations, and was controlled by programs on punched tape, which made it universal. This was the first computer capable of calculating complex numbers and performing aerodynamic wing calculations — exactly the task for which Zuse started all this seven years ago.
🚫 But the Nazi regime saw no strategic value in Z3. The Wehrmacht needed rockets, tanks, and aircraft, not "arithmometers for engineers." Zuse's application for funding was rejected by the Reichsforschungsrat (Imperial Research Council) with the wording "not critical for military needs." Helmut Schreyer, Zuse's colleague, tried to convince command to build an electronic version of the computer with 2000 vacuum tubes, promising speed 100 times higher, but was refused — the project was deemed too expensive and risky. The Third Reich lost the computer race without even realizing it had begun.
📜 While Berlin was turning into ruins, Zuse developed Plankalkül — the first high-level programming language in history, ahead of Fortran by a decade and a half. From 1942 to 1945 he wrote the language specification in notebooks, working in a workshop in Göttingen, where he evacuated Z4 and the remains of his equipment. Plankalkül supported data types (integers, floats, booleans, arrays), conditional operators, loops, recursion, even something like records and sets. Zuse described sorting algorithms, expression parsing, and chess playing in it — tasks that in 1945 seemed pure fantasy even to the ENIAC teams. But the language remained in notebooks: there were no compilers, Z4 supported only low-level commands on punched tape, and the world only learned of Plankalkül's existence in 1972, when the first publication appeared in a journal.
🕳️ The main tragedy of Plankalkül is not technical, but informational. The language was developed in intellectual isolation, without feedback from the scientific community, without the ability to test on real machines, without a chance to influence the mainstream of programming, which at that time was being formed at Bletchley Park, Princeton, and the University of Pennsylvania. When ALGOL, Fortran, and COBOL began appearing in the 1950s, Plankalkül was already a historical artifact — proof that the ideas of high-level languages were in the air, but they were implemented by those who had access to resources and an audience. Zuse tried to convince universities and the government of West Germany to fund a compiler in the 1950s, but was refused: the country was recovering from war, and programming was considered an exotic luxury.
🎭 The paradox of Plankalkül is that it was the correct answer to a question the world hadn't yet asked. In 1945 programming as a discipline didn't exist: ENIAC was programmed by rearranging cables, Colossus — by switches, early American machines — by machine codes on punch cards. The idea that a program could be written in a language close to mathematical notation and automatically translated into machine code seemed unrealistic. Zuse figured this out independently, but he had no tools to prove the viability of the concept. Z4 by 1950 had conditional jumps and subroutines, but never got a full compiler — the machine was leased to ETH Zürich and used for numerical calculations, not for experiments with languages.
🚂 In the spring of 1945, when the Red Army was approaching Berlin, Zuse loaded Z4 into an Opel Blitz truck, added a ton of punched tapes, tools, spare parts, and several crates of documentation, and headed south to the Bavarian Alps. The machine weighed nearly a ton, occupied the volume of a small van, and every bump on the war-torn road threatened to knock the relay settings out of alignment. Zuse drove 500 kilometers through ruins, bypassing refugee columns, checkpoints, and bombings. In the village of Hinterstein in the Allgäu Alps he hid Z4 in a barn and waited for the end of the war. The machine survived the capitulation, but remained invisible to the world: American and British intelligence were hunting for German rocket technologies, nuclear developments, and chemical weapons, and "engineer Zuse's computing machine" didn't even make the list of interesting finds.
🏔️ Z4 remained in the Bavarian wilderness until 1949, when Zuse received a contract from ETH Zürich — the Swiss Federal Institute of Technology, which was looking for a computing machine for the work of mathematician Heinz Rutishauser. The contract was modest: leasing the machine for 50 thousand Swiss francs per year, staff training, technical support. Z4 became the first commercial computer in Europe — two years earlier than the British Ferranti Mark 1 and three years earlier than the American UNIVAC I. But few knew about this: the Swiss didn't advertise the deal, Zuse had no budget for PR, and the Anglo-American press ignored the developments of a "former Nazi." Z4 worked at ETH until 1955, performing thousands of hours of calculations for aerodynamics, statistics, and engineering projects, but never received recognition beyond a narrow circle of Swiss scientists.
⏳ Only in the 1960s did the Western world begin to recognize Zuse's priority. Computer historians stumbled upon Z3 documents, reconstructed the chronology, compared it with ENIAC (1945, 18 thousand vacuum tubes, 30 tons, 140 kilowatts, decimal arithmetic, programming by rearranging cables) and acknowledged that the German machine was four years older, more compact, more economical, and closer to modern architecture. But this verdict was academic: American ENIAC and British Colossus had already become symbols of victory over Nazism and Western technological superiority, and Zuse — an uncomfortable reminder that geniuses are born regardless of political regime, but survive only with resources and freedom of communication.
🌍 If Z3 and the documentation on Plankalkül hadn't burned in 1943, the postwar world could have gotten a computer revolution on a German technological foundation — but only under one condition: Germany's capitulation would have had to happen before the bombs destroyed the infrastructure. Imagine: the Allies capture Berlin in 1943, find Z3 in the basement on Methfesselstrasse, take the machine along with Zuse to the USA or Great Britain. There his work falls into the hands of the ENIAC and Colossus teams, merges with American and British developments, and by 1950 the world gets a generation of computers combining Zuse's relay architecture with von Neumann's vacuum tubes. Plankalkül is implemented as a compiler, becomes the basis for early programming languages, and Fortran appears not in 1957, but five years earlier.
🔥 But reality is brutally simple: war destroys not only people, but ideas. Z3 burned, Z1 and Z2 also turned to ash, Z4 survived by chance but remained cut off from the world scientific community. Plankalkül lay in the archive for 27 years, ETH Zürich used Z4 only for numerical calculations, and the Western computer industry developed along a parallel path, ignoring German experience. Zuse founded Zuse KG company in 1949, released a series of commercial computers Z11, Z22, Z23, but lost the competition to IBM, Ferranti, and Univac — the giants had access to postwar American investments, military contracts, and the global market, while Zuse remained a local player in the West German market.
📌 Today Zuse's name is known mainly to specialists. Z3 exists as a 1962 reconstruction in the German Museum in Munich, a 2001 reconstruction at the Free University of Berlin, and a 2021-2024 version assembled by Christoph Thaber in Switzerland. Z1 was reconstructed at the Berlin Museum of Technology in 1989 by Zuse himself before his death. Modern engineers study his machines as a curiosity — proof that binary architecture and program control were invented not at Bell Labs and not at Princeton, but in the basement of a Berlin apartment by a man who was simply tired of calculating by hand. Plankalkül has been implemented in several educational compilers, used in courses on the history of programming, but left no trace in the mainstream. The German computer revolution remained a footnote in textbooks — another story about how political isolation, military destruction, and lack of communication kill innovation faster than any censorship.